Fast Pathogen Identification Using Single-Cell Matrix-Assisted Laser Desorption/Ionization-Aerosol Time-of-Flight Mass Spectrometry Data and Deep Learning Methods

Anal Chem. 2020 Jun 2;92(11):7523-7531. doi: 10.1021/acs.analchem.9b05806. Epub 2020 May 11.

Abstract

In diagnostics of infectious diseases, matrix-assisted laser desorption/ionization-time-of-flight mass spectrometry (MALDI-TOF MS) can be applied for the identification of pathogenic microorganisms. However, to achieve a trustworthy identification from MALDI-TOF MS data, a significant amount of biomass should be considered. The bacterial load that potentially occurs in a sample is therefore routinely amplified by culturing, which is a time-consuming procedure. In this paper, we show that culturing can be avoided by conducting MALDI-TOF MS on individual bacterial cells. This results in a more rapid identification of species with an acceptable accuracy. We propose a deep learning architecture to analyze the data and compare its performance with traditional supervised machine learning algorithms. We illustrate our workflow on a large data set that contains bacterial species related to urinary tract infections. Overall we obtain accuracies up to 85% in discriminating five different species.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aerosols / chemistry
  • Deep Learning*
  • Gram-Negative Bacteria / cytology*
  • Gram-Negative Bacteria / isolation & purification
  • Gram-Negative Bacteria / pathogenicity*
  • Gram-Positive Bacteria / cytology*
  • Gram-Positive Bacteria / isolation & purification
  • Gram-Positive Bacteria / pathogenicity*
  • Single-Cell Analysis*
  • Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization

Substances

  • Aerosols